For residential metering systems, more and more utilities today are using electronic metering devices. Electronic meters are cost effective and provide the utility with measurements of a number of electrical parameters. A function that many electronic metering devices provide is the ability to include whole house meter disconnect switches. These switches offer a utility the ability to disconnect power from the residence without visiting the site. This remote operational capability saves money and reduces manpower. For example, a utility may need to disconnect service when a subscriber moves out of a particular location and then later reconnect service to the same location when another subscriber moves in. Likewise, utility companies are sometimes forced to disconnect service to a subscriber who does not pay, and then reconnect service when the subscriber's account is settled. A number of electronic metering devices currently exist that provide connect/disconnect capability through the use of disconnect switches internal to the meter.
When a metering disconnect switch is operated by a motorized driver, there is some uncertainty regarding the total travel of the switch, since the motor's travel is dependent on the applied voltage and the time the voltage is applied. For different temperature and load conditions, the motor may travel faster or slower.
One technique for determining the position of a meter disconnect switch is load-side voltage sensing. After a command to disconnect power is issued to a meter disconnect switch, the meter may use a sensor to determine whether load-side voltage is still present. When the disconnect switch is properly open, there should be no load-side voltage detected. If load-side voltage is detected after a command to disconnect power has been issued to the disconnect switch, an error condition may be reported.